


First Impressions

by nan00k



Series: Small World [2]
Category: Good Omens - Neil Gaiman & Terry Pratchett, Sherlock (TV), Supernatural
Genre: Demon!Sherlock, Gen, Superwho, Superwholock
Language: English
Status: Completed
Published: 2013-01-13
Updated: 2013-01-13
Packaged: 2017-11-25 08:55:38
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 12,663
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/637202
Author URL: https://archiveofourown.org/users/nan00k/pseuds/nan00k
Summary: <blockquote class="userstuff">
              <p>John needs a roommate; what he doesn't need is a roommate who's eccentricity is less of a problem than his superhuman nature. A peek into the world of crime solving as well as the realm of the supernatural leaves the doctor an interesting choice. (Superwholock, AU demon!Sherlock. Part of the "Small World" series.)</p>
            </blockquote>





	First Impressions

**Author's Note:**

>   
> **Warnings** : MASSIVE crossover, mixing of canons, alternative universe setting, dark themes  
>  **Disclaimers** : _Good Omens_ © Pratchet and Gaiman. _Sherlock_ © Moffat/Gatiss. _Supernatural_ © CW/Kripke.  
> 

**Six Weeks Ago  
London, England**

"You need someone else."

"No, I do not."

"I can't keep an eye on you all the time, Sherlock, if you insist on doing these detective cases."

"I don't need a keeper."

"Crowley—"

"Is in America, doing Lilith's business."

"Sherlock, listen to me. I know you're bored. If you act out and they see you, they'll find us both."

"Hell can't touch you."

"Maybe not, but my superiors aren't pleased with me either. The deal was to lay low here."

"And so we are."

"Sherlock, you need a better cover. You're a sore thumb out there, wandering around with the police. What if you have to slip cover to protect yourself? You need more than just the guise of a genius."

"…I'll get a cover."

"Make sure it sticks."

"Even if it is a human?"

"…Even if."

**0000**

**St. Bart's Hospital  
Smithfield, London**

Three suicides. A fantastical case, indeed. It was obviously a case. Human nature was terribly obvious sometimes. It was only the particular perpetrator or perpetrators that were mysteries waiting to be solved. Sherlock enjoyed the hunt for them immensely.

 _Wrong. Wrong._ As much as Lestrade could be quick when it came to certain matters, he trusted police protocol far too much when it came to cases. It was a shame, really. His skills as a hunter could have given him the advantage over the average crook, but Lestrade had always been afraid of his shadow. That left it to Sherlock to pick up the pieces when the police failed to notice the signs of a fascinatingly dangerous new case.

Suicide epidemics. It was unheard of, even for Sherlock, who had quite literally seen it all in his time on Earth. Serial killers were fun, sure, but serial suicides prompted a deeper question. It couldn't be proven, but he could feel it in his gut. Time working for the police over the last year and a half had given him new insight into his senses. He could feel when cases would expand into something this absurd. This one would be a big one.

It was a worthwhile distraction, even as he waited for the police to catch on, or for the next body to show up, because goddamn that angel. Sherlock had been forced to escape into the outside world earlier and earlier to escape his nagging housekeeper's critiques.

Doing anything outside Baker Street, with all its lovely wards and sigils burned into the wood unseen, was a danger. He could have been having tea in the most insignificant of stores and be spotted by a member of the heavenly or demonic bodies. He stood out like a sore thumb, just like any demon would have to a creature of the supernatural.

No, the angel had insisted, this was different. Running off and doing cases was dragging Sherlock Holmes into the spotlight. What if he had gotten into the papers, with his face all over the place? What if one of his clients or targets had a connection to one of their enemies? Or even one of the hunters?

Sherlock knew all of those risks when he had approached Lestrade and signed himself up as a consultant. Being an idiot was Lestrade's job, not Sherlock's; he took all the precautions he could. He avoided cases that stank of magic or darker forces. He scouted those he interviewed when he could, just to make sure they didn't have a reason to identify him as Zephyr the West Wind.

Having a human around on those cases… what good would it do Sherlock? The human would have to be introduced to him and the world of the occult, and that was a danger in and of itself. Scouting for humans who didn't fear monsters was almost impossible to contemplate.

Crowley had jokingly suggested finding a hunter. _A hunter._ Sherlock all but threw his cell phone out the window after that conversation.

A human might have been a good deflective shield, true, but finding the right one who was trained for the job seemed an unlikely event. Sherlock knew the odds were against him.

So, he ignored his house lady and went straight to work. He was almost finished wrapping up the fish farm patricide case and he felt no need to hurry with it other than the uncle already being in police custody. It was a decent distraction from Sherlock's impossible task plus the wait for the next lead on the suicides.

Patience was never one of his better qualities. Mycroft would have said he didn't have any better qualities, but neither did Mycroft for that matter.

Sherlock had just settled into the lab tucked away in St. Bart's when the door opened and broke his solitude. He already knew who was hobbling down the corridor, of course; the gait was unmistakable. It was also six in the morning, so not many others would bother him or his work.

The human who had entered was Mike Stamford. An old university colleague. One of the few humans who knew Sherlock's name and bothered to remember it. A convenient thing, since he was the lead assistant at St. Bart's chemistry lab and was always willing to lend the school's services to "an old friend." Sherlock wasn't sure he qualified as one of those, but Stamford was intelligent enough to know Sherlock was not merely an amateur chemist. He knew what he was doing.

"Morning, Holmes," Stamford announced, shuffling into the room. He gained nearly two stones in the last month, Sherlock noted. Problems with the wife continued, clearly.

Sherlock kept his eyes on the skin cells. "Morning."

Dropping a pile of papers onto the counter, Stamford glanced deliberately at the quiet man. "You look a bit run down. Coffee?"

The detective looked up briefly at the human and considered him as a possible candidate for the angel's suggestion.

Stamford was fifty-six; overweight, bad knees. Sherlock sighed and looked away. Useless on the field.

Used to Sherlock's silence, Stamford went about moving through the lab. "You're in here real early. House lady kick you out finally?" he joked. His laugh died off quickly when Sherlock didn't acknowledge him. "Ha, sorry."

"No," Sherlock replied in a drawl. He switched slides. "But she has requested I find a roommate. How ridiculous."

Not a roommate in so many words, but Sherlock couldn't keep friends well. This one would have to be permanently attached to Sherlock's life somehow. Living together would have been the only option.

"Problems with rent?"

Sherlock hid an eye roll behind the microscope. "Yes."

"Well, I'm sure you could find someone real quick. Nice property, nice location."

"Ah, yes, but who would ever want me as a flatmate?"

He adjusted the dial just slightly—ah, yes, there it was. He jotted downs something on a tablet of paper without moving away from the microscope. This would help prove the daughter wasn't involved, but he still needed to clear the uncle.

He'd have to speak with Molly soon; bruises didn't materialize on their own. It was very convenient to have a source of corpses on hand, though it was nothing compared to medieval Europe. It was a pity he had never thought to start detective work back then, but honestly, it wasn't like there had been the sort of crimes that would have intrigued him this much back then…

Stamford had put his chart down and seemed like he had been waiting for something. Sherlock ignored the silence that carried.

"Well, if I hear anything I'll let you know," Stamford said, always bright. He was referring to the flatmate thing again? How odd. "I'm going to go grab some breakfast. Want anything?"

Sherlock underlined his verdict twice and shifted the slide down. "No."

That had been the one thing Sherlock had never been able to master growing up human—how to make and keep friends. Stamford was either enamored with Sherlock's intelligence or was simply so dimwitted that he honestly didn't mind Sherlock's briskness. For most people, they were turned off in time by Sherlock's inability to outwardly care about them personally. Actually, except for a handful of them, he really didn't care for most humans inwardly either.

His curse would always be the fact that no matter how much he analyzed and knew of human nature, he was not human in nature himself. Returning gestures was difficult to do as instantaneously as the humans could. How could he mimic what was a part of biology, after all? Emotions were so intricately connected to the body for humans; he could never truly learn to mimic it. It had long since proven to be a hindrance in keeping up appearances as a regular human, hence the need for the damn flatmate.

The lab door shut soundly. Sherlock worked on and already disregarded the conversation as irrelevant to his needs.

**0000**

With one slide of human skin cells under the microscope and waiting for the bruises to materialize downstairs, Sherlock paused in his examination to answer the buzz of his phone.

 _You still at Bart's?_ -MS

Stamford. Sherlock considered the message for a careful moment.

 _Yes. Why?_ –SH

 _Stay there._ \- MS

Sherlock paused. Stamford was an idiot, but he had enough sense not to bother Sherlock with inane requests.

He was already there, he reasoned, so waiting for any surprise from the chemist wasn't a setback.

Interesting.

**0000**

The lab door opened quietly. Two men walked inside, but Sherlock already knew who they were. Stamford's wheezy breathing was easy enough to identify. The mere fact that Stamford had brought with him another man, who was not a Bart's employee, could only mean one thing.

Sherlock glanced to the side. What he saw was enough.

Human. Wounded, yes. But the dependency on the limp wasn't permanent. The way he held himself suggested recent combat, so a hardened soldier.

That was a rare find in London. Sherlock hid a smile.

"Bit different from my day," the stranger said, looking around the room with vague interest. Not terribly concerned with actually paying attention to the lab or the equipment. Polite. Obviously had a medical background.

Army doctor, then.

Stamford was looking expectantly at Sherlock behind the stranger, waiting for Sherlock to make the first move, naturally.

It was an unknown situation, but Sherlock was curious. He glanced at Stamford. No jacket. The human's habits were easy enough to remember.

"Mike, can I borrow your phone?" he asked, focusing on his work in front of him. "There's no signal on mine."

"And what's wrong with the landline?"

"I prefer to text."

He knew the strange man—plaid shirt, simple worn jacket, clearly not an employee of Bart's—was paying attention to their dialogue, and to Sherlock. Perhaps Stamford had told this man about Sherlock's need for a roommate. He wasn't asking questions or introducing himself right away, but the careful testing of waters was fine by Sherlock.

"Sorry," Stamford said. "It's in my coat."

Naturally. It always was. Sherlock waited, carefully measuring the sample out.

It took only a few seconds. Polite; the stranger cleared his throat.

"Uh, here." He rummaged in his jacket pocket. "Here, use mine."

Sherlock turned and looked at the man.

"Oh," he said, gauging the honesty in the human carefully. There was little care about handing the phone over; a disinterest in it, as if it were only a sparse handkerchief. Sherlock stood. "Thank you."

"This is an old friend of mine," Stamford said, pointing over at the stranger. "John Watson."

John, a biblical name. Sherlock walked over to retrieve the phone and saw that the polite smile on John's face was a tad forced. Discomforted. By the association with Stamford? Or just over being introduced? He didn't seem like a shy man, however. Just polite disinterest in being there.

That wouldn't do. Sherlock flipped the hone open before asking, "Afghanistan or Iraq?" _Oh_ , this phone revealed so much about the man. It was excellent.

Stamford just smiled.

It took a beat. John slowly turned his head back toward Sherlock, standing just a few spaces back, and asked, "Sorry?"

Sherlock turned his head to meet his gaze briefly. "Which was it, Afghanistan or Iraq?"

There was another silence, as John clearly took a moment to consider how Sherlock had known. Sherlock was used to it. He patiently typed the message out ( _how did the police miss that green ladder, honestly?_ ) while John looked to Stamford for confirmation, but the other chemist just smiled. Molly entered the room during the pause.

"Afghanistan," John replied at length, shifting on his legs. "Sorry… how did you know?"

Sherlock cheerfully ignored the question by accepting Molly's offered coffee. "Ah, Molly, coffee. Thank you."

John stared out as Sherlock shooed the poor woman away. Sherlock took a long sip of coffee—she wasn't too bad at making it, far better than Hudson—before returning to his workstation.

"How do you feel about the violin?" he asked.

There was another pause, simply because John thought he hadn't been speaking to him. He was quick, however, to turn back and fix Sherlock with a bewildered expression.

"Sorry, what?" the human asked, shifting again on his leg, favoring the wounded one.

"I play the violin when I'm thinking," Sherlock replied simply. "Sometimes I don't talk for days on end. Would that bother you?"

It drove the angel nuts, but Sherlock wasn't sure what to expect from John Watson, who, despite being obviously confused, wasn't reacting like most would. Calm, then. Sherlock liked calm humans.

John's eyes were squinted, but he just stared at Sherlock, waiting for more information. Rational. Perhaps not as quick as Sherlock had hoped.

"Potential flatmates should know the worst about each other," the detective continued with a short smile.

John looked at him, hard, before looking back to Stamford. "You told him about me?" he asked.

"Not a word," Stamford replied, amused still.

"Then who said anything about flatmates?" John asked, barely rhetorical, looking at the table before looking back up at Sherlock. The human didn't like awkward social situations. He wasn't comfortable with the idea of needing a roommate. Curious.

"I did," Sherlock replied, grabbing his coat. The results from the samples were as he suspected. "Told Mike this morning that I must be a difficult man to find a flatmate for. Now here he is just after lunch with an old friend clearly just home from military service in Afghanistan." He wrapped his scarf around his neck neatly. "Wasn't a difficult leap."

"How did you know about Afghanistan?" John asked, suspicious. Didn't trust Sherlock's ability to discern information. He struck Sherlock as a quick learner, however; he'd understand soon enough.

Sherlock ignored the question. "I have a nice little place in Central London," he told the soldier. "Together we ought to be able to afford it."

It wasn't about money, but for humans, money was always a simple, easy excuse.

"We'll meet there tomorrow evening, seven o'clock," he told John, stopping short of the man. He smiled briefly. "Sorry, got to dash. I think I left my riding crop in the mortuary."

He moved around the human, who looked unsettled. A slow thinker, slow reaction. That could be a benefit. The louder humans were in simple situations, the more tendency they had to scream when things actually became dangerous.

Sherlock felt a great deal more confident about this match up. A calm former army doctor would be the perfect companion. Lestrade would be happy, the angel would be happy, and hopefully Crowley would stop complaining. With a medical history, perhaps this Watson could be of some rudimentary assistance during cases. Better than Anderson or his ilk, that was for sure—

"Is that it?"

The abrupt, loud question had Sherlock stop at the door. "Is that what?" he asked.

"We've only just met and we're going to go and look at a flat?" John asked, suspicious again visible. Careful humans were rare. It was intriguing.

"Problem?" Sherlock prompted, gauging his reaction.

John looked at Stamford, who said nothing, before looking back at Sherlock. The defensiveness was surprising, but when he spoke, John revealed he was gauging Sherlock just as much as the demon was him.

"We don't know a thing about each other. I don't know where we're meeting. I don't even know your name," he said.

Sherlock tilted his head slightly, enjoying the moment of disbelief before he proved someone wrong. Stamford clearly hadn't warned him. Good.

"I know you're an army doctor and you've been invalided home from Afghanistan," he began, giving John no room to interrupt. "I know you've got a brother who's worried about you, but you won't got to him for help because you don't approve of him, possibly because he's an alcoholic, more likely because he recently walked out on his wife." The growing look on John's face fueled the fire. "And I know your therapist thinks your limp's psychosomatic—quite correctly, I'm afraid."

John _stared_ at him.

"That's enough to be going on with, don't you think?" Sherlock asked, enjoying every second that passed, revealing a streak of surprise in the human's expression.

He wasn't expecting it to fall back into a hardened stare. It wasn't that surprising. A man of John's background—emotions were easy to reign in. Sherlock opened the door and felt a flare of confidence in the silence that followed.

This one might work.

"The name's Sherlock Holmes," he said, turning his head, "and the address is 221B Baker Street."

He winked. John just stared harder. Stamford waved and Sherlock let the door shut behind him.

If Watson showed up, Sherlock thought as he marched down the hallway pleased, this one might definitely work.

**0000**

**221B Baker's Street**

The flat was nice. Really nice, actually. Right next to a café, plenty of transportation around… it was really nice.

That's what made John uneasy. Not that the place was nice, or that the landlady was willing to accept such a low rent payment from them both for such an amazing real estate find in the city, but the fact that the whole situation was… too nice.

Kooky roommate, yes. The fact that the man had gotten such a good deal from the landlady—Mrs. Hudson was a pleasant woman, albeit a bit unsettling with the whole husband-thing-in-Florida—was suspicious. He assumed Sherlock was a private eye, but he lacked the professionalism for it.

Sherlock had already moved into the place. It seemed…well lived in. If he had needed a roommate, how long had he lived here before?

The mess was easy enough to fix, though John had his suspicions that Sherlock wasn't exactly the neatest flatmate. That was forgivable.

Just… the weirdness. John couldn't shake a deep sense of…not unease, but certainly wariness whenever he was alone with the other man. Sherlock was intimidating. And a little creepy. John was still trying to figure out how the man had figured out about Harry, or hell, even his leg.

"What do you think, then, Dr. Watson?" Mrs. Hudson had asked. She had pointed upwards. "There's another bedroom upstairs, if you'll be needing two bedrooms."

John had done his best not to react too much to that. "Of course we'll be needing two."

"Oh, don't worry, there's all sorts round here," she had replied, as if sympathetic. "Mrs. Turner next door has married ones."

 _ **Okay**_. At that, John had turned and sent Sherlock an exasperated look. The taller man skillfully ignored it. What the hell had he told his landlady…?

The information he had found online did very little to assuage John's doubts, but he had to admit, it was… interesting. A bit of bollocks about the deduction stuff, but John was intrigued by Sherlock's fervor. It was all very interesting. Odd, yes.

What wasn't so interesting as it was alarming was Sherlock's ability to read him. About Harry. His leg. His career…

 _How?_ It was incredibly unnerving.

Just when he thought it couldn't get any weirder, the cops showed up. John had watched, astonished, as the police asked Sherlock for assistance on a case that sounded unnervingly like the case he had seen in the paper. Sherlock all but gave the cops the cold shoulder, but when they left…

"Brilliant! Yes!" the dark haired man had yelled, his face lit up like a child on holiday. "Four serial suicides and now a note. Oh, it's Christmas!"

It _was_ the case. John sat down cautiously and didn't say anything. Maybe this was a mistake. Maybe it wasn't. He had never lived with a private detective before. Maybe…it would be interesting to experience from the sidelines.

Anything was better than the rest home. John didn't have much room financially to shun this opportunity either.

Sherlock had jumped around for his coat and scarf, still gleeful. It was bizarre.

"Mrs. Hudson, I'll be late. Might need some food," the man said as he tied his jacket tightly closed.

Mrs. Hudson sent him a pleasant smile. "I'm your landlady, dear, not your housekeeper."

"Something cold will do." Sherlock paused long enough to send John a deliberate look. "John, have a cup of tea, make yourself at home."

With that, he was gone, out the door in a flurry of action.

"Look at him rushing about…" Mrs. Hudson murmured once it was just the two of them left. She smiled down at John and started to head for the kitchen. Her motherly attitude was choking. "You're more the sitting down type, I can tell. I'll make you that cuppa, you rest your leg."

"Damn my leg!" he yelled, fire in his gut roaring. He squashed it instantly, the rage nothing more than a phantom reaction. He immediately looked down. "Sorry, I am so sorry."

The housekeeper, despite looking a bit frail, had only jumped at the sudden exclamation. She didn't look like she begrudged his outburst.

"…I understand, dear," the woman said at length, sympathy in her eyes. It made John's stomach ache.

"A cup of tea would be lovely, thank you," he said, sighing heavily. Trying to exhale phantom burns didn't quite work.

Mrs. Hudson smiled like she had at Sherlock and sashayed out of the room. "Just this once, dear. I'm your landlady, not your housekeeper…"

John wanted nothing more than to…to… He grabbed a newspaper and saw the blaring headlines about the suicides. He couldn't even read anything. He wondered where Sherlock would even go. The man seemed to know what to do, even without a police guide.

What a strange man. No stranger than a wretch like John was now, of course.

An odd feeling crept up his back while he sat there trying to force his brain to compute printed text again. John looked up and saw a surprising figure in the doorway: Sherlock. The detective looked unruffled now and calm. He was watching John with a startling intensity. It was like being stared down by a statue. John stared back.

"You're a doctor," Sherlock stated in a way that wasn't exactly a question. "In fact, you're an army doctor."

John frowned. "Yes."

"Any good?" Sherlock asked.

A part of him suddenly stopped feeling apprehensive. "Very good," he replied automatically, without hesitation. He was damn good.

"Seen a lot of injuries, then?" Sherlock asked, a pallor vision in the doorway. As he spoke, the room seemed to grow smaller and smaller. "Violent deaths?"

Wars were all the same. "Yes." There was always violence and always death.

"Bit of trouble too, I bet," Sherlock said, something dark tinting his words. It wasn't threatening.

"Of course, yes," John said, steeling his nerves. "Enough for a lifetime, far too much."

There was a fire, a spark, in the base of his stomach. It had been there for months. It twitched and it tingled on days where things moved slower than they normally did. He had thought he had gotten used to it being there.

"Want to see some more?" Sherlock asked, eyes full of dark mischief.

That was all it took to make the spark jump into a flame. John didn't have the will power to resist it. Not then.

"Oh, God, yes," he said, meaning it wholeheartedly.

He never wanted anything more in his life.

**0000**

**Brixton, Lauriston Gardens**

Lestrade had just started to zip up his scrub jumper to head back up to the crime scene when he saw a familiar tall, dark figure saunter in from the outside. Sherlock Holmes was becoming a familiar sight, invited or not, God help him. Lestrade had meant to just nod his head in greeting, happy that the man had agreed to help him with this newest suicide, but he stopped short.

There was another man with Sherlock. A shorter, older looking gentleman with a cane. Even without the cane, it was clear this wasn't a police officer. Lestrade was immediately on edge. Sherlock didn't bring company. Sherlock didn't have company.

It wasn't Aziraphale or Crowley either. Lestrade's unease soon grew to actual discomfort.

"You should wear one of these," Sherlock said, pointing to the scrub suits. The unknown man agreed willingly and grabbed a jumper.

"Who's this?" Lestrade demanded. The stranger didn't look familiar at all. That never, _ever_ boded well.

Sherlock barely looked at Lestrade. "He's with me."

Lestrade turned and frowned. "But who is he?"

"I said," Sherlock replied, with a far cooler tone, "he's with me."

That could have meant not-human. But it could also have meant weird-human. But never normal-human. A hunter? Lestrade eyed the awkward newcomer carefully as they slipped on their boots. Sherlock didn't need to bother since, well, he never left any sort of trace anywhere, that inhuman menace.

This man, a Doctor John Watson apparently, seemed normal-human. Which made no sense. Lestrade felt nervous letting the man accompany them to the crime scene as Sherlock all but encouraged the man to be involved.

Sherlock had _insisted_ on having this Dr. Watson involved. He enjoyed Watson's reactions and questions, unlike how the demon reacted to Anderson or Lestrade's questions about obvious things. Sherlock didn't have friends, or colleagues. Not ones that didn't know about the truth. But Dr. Watson seemed new to it all…including Sherlock.

The man was staring at Sherlock, whenever he spoke, with awe. Lestrade knew that expression all too well. It made his stomach churn with unease.

Sherlock wouldn't do something wrong—not like this. Not with Crowley and Aziraphale involved, no matter where the freaking demon was at this stage in the game. Lestrade watched Sherlock carefully.

He hoped it wasn't what he thought this was.

Lestrade watched Sherlock pull his magic over the corpse—a Mrs. Jennifer Wilson—and Watson follow the information as best he could. Lestrade knew he should have been paying closer attention, but the suicides had faded in his mind.

After a few minutes of babbling, Sherlock did something he never did: he asked Watson to form his own opinion on the dead woman's demise.

 _Okay, that's enough_. Lestrade cleared his throat and motioned for Sherlock to step out of the room with him. Anderson had fled, thankfully, and they were alone on that part of the landing.

Irritated at being summoned away from his corpse, Sherlock humored Lestrade long enough to step out of the room with him. "Yes?"

"What's with the guy?" Lestrade asked quietly, eyes going to Watson's back.

"I told you—"

Lestrade moved closer, voice dropping lower. "What's the deal with a _human_?" he asked in a hurried whisper.

Sherlock's eyes darkened. For a moment, Lestrade almost expected the man to become angry. "…You can assure yourself, Lestrade, that there's nothing's wrong with this," the demon replied, voice far too careful.

It would have been a mercy to let it go. But Lestrade had been raised a certain way. That way had mostly involved never trusting monsters.

"You know I can't just…" the police officer began, eyes going between Sherlock and Watson. It just didn't seem right.

"I needed a flatmate. He offered. I offered the trip down here. He was interested." Sherlock's pale lips quirked upwards and his eyes darkened. "Mrs. Hudson wholeheartedly approves."

 _Mrs. Hudson?_ "Oh, bloody…" Lestrade ran a hand over his face, exasperated. "Who the heck would be interested in a murder scene?" Besides consulting detectives.

More importantly, what the hell was this _flatmate_ nonsense? Those two unnatural walking disasters didn't need human roommates. They didn't need to pay a mortgage and they needed privacy far more. This was about something else.

"I don't know, Lestrade," Sherlock replied, voice going higher in sarcastic pitch. "Maybe he's just as disturbed as _you_ are."

The jab made Lestrade scowl. "Sherlock."

"What?"

There was a brief moment of his father's words screaming in his ears, that Lestrade should have just forced the demon to behave. Demons were one thing, however. Sherlock had made plenty of allies in high places (never friends, of course.)

"Don't do anything stupid," Lestrade said, the call to act fading as he realized he didn't have much say in policing Sherlock's actions anyway. He was so far beyond the law that it was laughable whenever Anderson or Donovan begged him to arrest Sherlock.

Sherlock's smirk widened as he turned back to face Watson. "Or force your hand? My dear Lestrade, why would I ever want to do a thing like that?" he asked, mocking. He stepped away and went back into the room, all too ready to listen to Watson's basic deductions about the crime.

He was being too lenient.

Both of them were. The leniency on Sherlock's part was more troubling than Lestrade could really handle at this point.

"Pink!" Sherlock eventually exclaimed, leaving the others floundering, as usual. The case had a much sourer feel to it now that Lestrade had other worries than serial suicides to think about.

Watson followed the consulting detective like an eager puppy. It reminded him of the Young boy all over all. Lestrade grimaced as Sherlock took off and Watson hobbled his way after him.

It wasn't just Sherlock who had to be worried about repercussions. Lestrade tucked his hands into his pockets and exhaled sharply.

He certainly hoped Aziraphale knew what the hell he was doing with this.

**0000**

Somehow, they wound up having dinner together. John was still trying to figure out how that happened.

He was still uneasy about everything that had transpired in the last twenty-four hours. First, he had seen a dead body. Then, he was abducted by some apparent nemesis that Sherlock had. And then, of course, Sherlock continued to amaze and terrify John every step of the investigation John somehow found himself wrapped up in. A serial suicide investigation.

To think, last week, he had been complaining about being bored.

John had never expected it to go as far as it had. Texting a murderer? It was enough to make him jumpy.

_You don't seem very afraid._

The nemesis man had said that with a smile, as if he were issuing a challenge. John wasn't a competitive man, but there was an undeniable thrill that went through his gut as that night went on. It wasn't a happy thrill. Death, mystery, and potential criminal activities didn't incite happy feelings.

But there was thrill. John knew it was probably counterproductive to the work his psychologist had put into him, if any existed at all, but right now, he didn't care.

_What is your connection to Sherlock Holmes?_

John stared across the table at his dinner partner, who was in fact not eating anything. He knew nothing of Sherlock Holmes. Not really. The man was bizarre. He seemed too intelligent to be a nobody, but yet, he didn't seem to really exist anywhere. He stood out like a sore thumb. He didn't belong to the environment they were in.

_Since yesterday, you've moved in with him and you're solving crimes together._

Technically, he hadn't quite moved in yet, but maybe the nemesis had a point. Maybe it was a bit fast.

_You're very loyal, very quickly._

John took a sip of drink.

He was. Maybe that wasn't such a good thing.

Sherlock _was_ sort of an ass.

"Do people usually assume you're the murderer?"

"Now and again, yes."

John stared down at his left hand. It had twitched a bit, but it was mostly still for the duration of the meal.

Maybe it was just coincidence.

Whatever his issue was, he was there, with Sherlock at that restaurant, waiting for a murderer to show up. Genius needed an audience. Sherlock was more than enough evidence to sway John to believe it.

Sitting there, John had time to contemplate things. He had time to ask questions. He avoided obvious ones, like why everyone assumed John was his bloody date. Questions about real people with real arch-nemeses were more common, if such conversation was common at all.

Conversations about boyfriends, however, made John realize that no matter how much of a genius Sherlock was, John was a ruddy idiot with a foot stuck solidly in his mouth.

He could handle pretty much anything else that came up after that.

Or so he thought.

"There," Sherlock announced. "Taxi, stopped."

John turned in the restaurant seat and saw what Sherlock was talking about. A taxi, just like any other in the city, waited for them.

And suddenly, they were off. John found himself running for the first time in nearly a year out the door and onto the street. Sherlock did a spectacular rebound off of a car, but that barely fazed the detective, who flew across the London street in hunt of a blue taxicab.

John ran after him, though the soldier hadn't a clue why.

"I've got the cab number!" John called out fruitlessly when they stopped at where the taxi had just been.

"Good for you," Sherlock replied, eyes squinting shut in fierce concentration. "Right turn, one way, roadwork, traffic lights, bus lane, pedestrian crossing, left turn only, traffic lights!"

 _Oh, my God_ , John thought in the briefest of seconds when the other man took off. _He has a GPS in his brain._

He didn't understand why that wasn't as shocking as it should have been.

John braced himself and followed.

They ran up stairwells and shoved past pedestrians. John was already out of breath by the time they got to the roof of the first building, but it wasn't from the exertion of running. His heart was on fire, but his lungs felt like they were encased in ice. His nerves sparked under his limbs.

_Most people blunder round this city and all they see are streets and shops and cars. When you walk with Sherlock Holmes, you see the battlefield. You've seen it already, haven't you?_

John kept up, barely, as they tumbled down a fire escape. The whole metal structure creaked as Sherlock jetted down. His feet hardly touched the stairs while John's steps sounded like miniature cannon fire.

_Your therapist's got it the wrong way round._

Sherlock jumped the cap between the fire escape and another rooftop effortless. John had to throw himself. He lost time between them in the effort, but he made it. He stumbled briefly and started up running again.

_You're not haunted by the war, Dr. Watson._

His blood rushed in his ears. He could hear himself panting. Watching Sherlock jump another gap that seemed too far, John slid to a hesitant stop. He stared at the gap and then back up again at Sherlock, who was disappearing into the night.

John swallowed against the lump in his throat and backed up to get a running start.

_You miss it._

His leg didn't make the ledge. He slammed into the concrete and his knee clanged against a protruding metal pipe. John wheezed and hauled himself back up onto the roof.

_Welcome back._

John was all the way upright on the roof when he saw Sherlock nearing a gap to jump onto the other. It was too far a jump. John took off running, only faintly alarmed when he saw Sherlock wasn't aiming for the fire escape.

" _Sherlock_!" he shouted, alarm flaring when Sherlock did jump—and missed the other roof.

It was three stories down. John suddenly ran faster and nearly went head over heels over the ledge.

He made it just in time to see Sherlock reach the ground.

And land neatly on his feet.

John stared.

Standing upright, Sherlock brushed his sleeves and looked upwards. Through the hazy night air, John felt the gaze land on him directly. He could have imagined cold gray irises piercing across that distance and past the darkness that hid them.

The eyes were dark, though. Not shadowed.

They were black.

Suddenly, all the rush died out of John's body. He stood at the top of the fire escape, and for a moment, motion was a foreign idea.

It was something else that compelled him to slowly, slowly descend the stairs. Sherlock hadn't moved. He was watching John intensely. It didn't even look like he was breathing.

John felt his limbs tighten up as the distance between them closed. He was the one doing that, however. It was his choice to get closer. He felt a tiny voice, the kind of voice that rings out in the mind of a hunter going up against prey larger than himself, in the back of his head telling him it was a stupid move, but he ignored it.

_The bravery of the soldier._

In a matter of seconds, John was two meters away. Their target was getting away.

John didn't really care about that, not right then. Sherlock was still watching him. The only reason John knew he was alive was because he could see the faint outline of hot air being exhaled from Sherlock's nose.

His eyes were still black as coal, too.

"What are you?" John asked, the question blurting out before there was any time to filter or amend it. It felt too harsh out loud. His throat was burning and John took a deep breath to try to cool it down.

Sherlock didn't flinch. He didn't react.

"Odd," the detective abruptly said. His voice was rougher than it normally was.

"What is?" John asked. He cleared his throat, his mind flashing back to the fall and the subsequent discoveries. "That I noticed?"

Sherlock's head tilted to the side. His lips twitched. "That you're not screaming," he said. He sounded vaguely amused. "Most people do. When confronted with something beyond the realm of this world they are most comfortable with, or expect, most people scream."

John swallowed again. He felt numb all over.

"…I'm not most people," he said lamely. His eyes went to Sherlock's, but he couldn't keep his gaze there for long. "But… what…?"

Sherlock smiled. "Guess."

"I… I wouldn't know," John admitted.

He didn't know anything like this. This wasn't…normal. It wasn't…

His _eyes_ —Sherlock's eyes. John stared down into two soulless, black eyes. There wasn't any white left; just shiny, almost-liquid black holes that reflected the street light boldly. The rest of Sherlock remained the same; his smile was new, however.

"You have two options, Dr. Watson, so do make wise of the one you choose," Sherlock began, in the same cool voice as always. The eyes pinned John to his place. "Choice one is obvious: run. Don't mention me, don't think of me, or what you saw, and you may just have an ordinary life. Most people do, when this occurs. It hasn't happened often, but I can say, this is the choice most choose."

John felt his heart racing. "…And the other?" he asked, unable to tear his eyes away from Sherlock's.

He flinched when the black disappeared, almost like a second lid, and Sherlock's cold gray irises returned.

"Run with me," Sherlock said.

"What?" John asked, startled again.

Sherlock smiled. This time, the coldness was gone. It was almost an encouraging gesture. "We have a taxi to hunt."

And with that, he took off once more into the street. John stood there for a second longer, his mind racing, his heart pounding—

And then he took off after him, belatedly realizing how much easier this was without the bloody cane.

**0000**

After everything that night, they got the wrong taxi, too.

 _You have to be kidding me_ , John thought. He wobbled onto the sidewalk and felt the adrenaline rush leave him like a draining reservoir. _What a night._

Sherlock was in a great mood, even after they ran from the police. John had been up for a second wind, but he was almost at his limits when they finally stopped a few minutes from home.

John glanced at his companion as he regained control over his breathing. "You're… a mutant?" he asked, causing Sherlock to glance at him. "Super hero?"

That earned him a smirk. "I have been called many things in my long life, but never a hero, John," he replied. He spoke casually, even when his words were enough to sober John completely. "I am a monster. I am the very opposite of something pure, or holy."

There weren't many words that fit that description. None of them made any sense. "…a demon?" John ventured. He scoffed and tried to shake the icy feeling out of his hands. "Oh… come on. Y-you have to be…"

He swallowed hard when Sherlock slowed and sent him a long look. John gradually stopped walking in turn.

"Really?" he asked, knowing he sounded pathetic.

"Trust your gut, never your mind, when dealing with this sort of thing," Sherlock replied bluntly. He frowned when John barked out a laugh. "What?"

"You? Of all people? Telling me to not trust my mind?" John asked, chuckling. It wasn't a totally hysterical laugh. Not really.

Sherlock rolled his eyes—his normal, not-creepy eyes. "I would _hope_ most people wouldn't trust their own minds. They're so tiny and impractical, however, when it comes to the paranormal. It's better for them to go with instinct in those specific cases."

"Ah, well, there it is…" John frowned. He slowly started to walk, Sherlock following suit. The streets were almost deserted then, which was a blessing. "A demon. Really. Well… ah… why are you doing this?"

"Doing what?"

"Hunting down a criminal?" John tucked his hands into his pockets. He was still numb. "Shouldn't you—shouldn't you want them to get away with something like murder?"

Sherlock stared at him. John suddenly felt smaller.

"Sorry," he offered lamely. He didn't understand, but he knew he had crossed some sort of line. Maybe.

"I am…"

Sherlock stopped walking. John stopped and turned around to face the other man. Sherlock looked out of place, as usual, but this time, he seemed more alone. A beacon out on the sidewalk. Terribly alone.

"I am Sherlock Holmes. The world's first and only consulting detective. I hunt not for the sake of justice, but for the sake of hunting," Sherlock said, voice as sharp as his eyes as he met John's gaze. They were entrancing. "There are many sorts of monsters out there, worse or less so than myself." The gray eyes narrowed a fraction. "I may try to hide what I am… but I do not deny it. There is no reason."

It was practically a declaration. John didn't know what for, though. He watched the other man—other creature—and took it all in. It was too much to decipher then and there on the street, but John Watson was a practical man. He didn't try to sort out details when the details only complicated things.

He didn't mind complicated things, as long as he could take them as they were. Because there was nothing wrong with complicated.

"…All right," John said.

Sherlock flinched. "All right?" he repeated.

"Yes." John nodded. "All right."

"Just all right?"

John smiled. "Yes. Just… all right."

It took Sherlock a moment to react. He kept their staring contest on for a moment longer before turning away. They were at 221 Baker's Street already. John climbed up the stairs after him and mimicked a mostly-real collapse against the yellow walls of the foyer.

John looked up at the ceiling and didn't think of anything for a few seconds.

"You are brave, Dr. Watson," Sherlock told him, turning his head a fraction to look at the doctor.

Perhaps the mysterious nemesis had been correct, John thought in a daze.

_Bravery is the kindest word for stupidity, isn't it?_

John knew he should have run the other way, but he had never called himself the smartest man. He now knew such a being and it was right there next to him, at any rate.

"I'm curious," John replied, letting his head rest against the papered wall. "Besides… that was fun."

Sherlock turned and gave him a surprised look. John stared back and only offered a smile.

It took a moment, but both men laughed.

At least until Mrs. Hudson came rushing in.

**0000**

"You can't just break into my flat!"

"And you can't withhold evidence!"

It sounded like an argument they had had before, John mused, though nothing about the situation was amusing.

"It's a drug's bust," Lestrade said, all too happily.

Definitely not amusing. John watched as Sherlock failed to deny such a claim as being possible. Demons on drugs. Wonderful.

"This is childish!"

"Well, I'm dealing with a child."

John tried to stay out of everyone's way. He didn't want a part in—in this. How odd that he could stand running across rooftops, but this was uncomfortable. John frowned as he watched Sherlock pace and snarl.

"I will let you in on this case, but you can't go off on your own!"

He had to wonder what sort of relationship he and Lestrade had. They didn't seem like enemies, but maybe it was another case of a nemesis for Sherlock. Did any of Sherlock's enemies know about his eyes? Maybe they didn't. Maybe only friends did. Maybe that's why Sherlock didn't have any friends.

This night was starting to spiral out of control in so many different ways. John rubbed his eyes. He was exhausted.

"…we found her suitcase in the hands of our favorite psychopath," Anderson was saying.

"I'm not a psychopath, I'm a high functioning sociopath," Sherlock snapped back.

John dropped his face into his hands while no one was looking.

"We found Rachel," Lestrade said, catching both Sherlock and John's attention. The name that had been scratched onto the floor by the victim.

As John had vaguely suspected, it was Wilson's daughter. It would have to be someone worth emotional value to carve a name into the floor with one's own nail.

"Her daughter?" Sherlock abruptly asked, his face filled with confusing disgust. "Why would she write her daughter's name?"

His confusion was confusing. Rachel was dead, regardless. John sighed quietly as he understood. It was an important name to Jennifer Wilson, then. Obvious—

"That's not right," Sherlock said, which surprised John. "Why?"

"Why would she think of her daughter in her last moments?" Anderson asked, sardonic. "Yeah, sociopath, I'm seeing it now."

John wanted to back Sherlock up just as a default on that, but…

"She didn't think about her daughter!" Sherlock insisted. "She scratched her name onto the floor with her fingernails. She was dying. It took effort, it would have hurt."

"You said that the victims all took the poison themselves, that he makes them take it," John said, trying not to focus on how tired he was. "Maybe he talks to them. Maybe he used the death of her daughter somehow."

"Yeah, that was ages ago!" Sherlock asked, sounding practically insulted. "Why would she still be upset?"

There was a lull. John saw Sherlock continue to look insulted until the detective eventually noticed the silence and the stares. Lestrade looked away and Anderson looked smug.

John pursed his lips. Oh. Right.

Demon.

Sherlock only took a few seconds to realize he had misspoken, but apparently, he didn't know in what way.

"…Not good?" he asked, glancing subtly toward the doctor. As if asking for confirmation for something. Like his startling lack of empathy.

John swallowed hard. "A bit not good, yeah," he replied, trying to keep his cool.

"Yes, but if you were dying, if you'd been murdered, in your very last few seconds, what would you say?" Sherlock asked, eyes flashing brightly.

Memories came back harder and easier than John liked.

"'Please, God, let me live,'" John replied, without having to think much past those images.

Sherlock made a condescending expression. "Oh, use your imagination!"

John's jaw tensed. "I don't have to," he said simply. He kept his gaze equal with Sherlock's.

It took him a moment, but the genius eventually frowned and backed off. He went to muttering about cleverness and how Jennifer Wilson wouldn't have wasted her last bit of strength on sentimentality. It left the rest of them behind.

The police kept doing their search, real or not. Lestrade was talking with his underlings and Sherlock tried to move away to ramble about passwords. John watched him and thought.

The revelations he had endured that night were starting to hit home in a way he hadn't expected it to.

Somehow, black eyes became much more real.

There was talk of taxis and Anderson's face and Jennifer Wilson being clever. It was all too much. John missed the running.

"Don't know why it matters, if she still cared about her daughter or not," Sherlock was muttering. The computer was loading the GPS signal.

"Don't you know how to empathize with someone? Don't you know morals?" John asked. He wasn't sure why he was pushing this. He wondered why Sherlock was allowing it.

"Morality is no different than any other social convention," Sherlock replied shortly. He waved a dismissive hand before tucking it again under his chin. "Science, math, history, religion—I know it."

John hesitated. "But do you _understand_ it?" he asked, daring to lean closer to the space the detective had just been pacing in.

Sherlock stared out past his bridged hands. "You can learn to understand anything, John," he said quietly. "Nothing is impossible to learn."

"Even to be human?" John asked, before he could think better of it.

Sherlock stopped. He turned slightly and gave John a long look, his freezing eyes full of energy and promise of fast-paced motion he always demonstrated on a case. John stared back, realizing he was being just as closely observed.

Whatever Sherlock was about to say in reply to that was interrupted when the computer dinged. Instantly, the cold eyes were replaced by ones on fire; Sherlock devoured the information on the screen—before stopping once again.

"It's here," he said, sounding like he didn't believe it.

John was left flummoxed like the rest of the police and there was a mad dash to re-search the flat for the missing phone. It had to be there, logically. But Sherlock stood in the center of the room with his hands on his head, muttering furiously about how he couldn't have missed it. He never missed things. John could imagine him seeing everything happen at once better now; it was easier to imagine now that he knew the man was superhuman after all.

In the midst of it all, John wondered just how much Sherlock did see in the world around them. He wondered if the murders, or the threat of the murderer still being out there, actually bothered Sherlock. Probably not. But maybe—it wasn't too far of a stretch.

_You can learn anything, John._

Even fear? John wondered. He caught himself staring at the computer in a daze.

Did demons feel fear—or grief?

And then, all at once, he realized something was wrong. Very wrong. Turning, John sought out the few familiar faces—Lestrade, Mrs. Hudson, Donovan—

John froze.

"Where's Sherlock?"

**0000**

Humans were fantastic—both as victims, and as predators.

"Taxi for Sherlock Holmes."

It was brilliant. It was a brilliant ploy, a brilliant trap. This single mortal man—a dying man, all hollowed out on the inside—had led Sherlock on a round-about trip for days. All along it was a cabbie. Sherlock felt the customary rush of glee when he was finally face to face with his target. It had been a good run. He had enjoyed this one.

Until the human smiled and gave him an ultimatum out there on Sherlock's own doorstep. A challenge. A dangled lure.

"If you go and get the coppers now, I won't run," the cabbie said, too calm, too casual. "But you're not going to do that. Because I didn't kill those four people, Mr. Holmes. If you get the coppers now, I promise you one thing—I will never tell you what I said."

Sherlock, for a brief moment, felt a flare of danger rush through him. Did this human not understand whom he was challenging? An ant dangling threats to a hungry spider? The gall.

But the cabbie didn't know, nor did it matter. Sherlock's scorn over the bold challenge was too weak to resist the lure. His one human weakness—curiosity.

He held back, however, long enough to remember where he was and who was back inside Baker Street.

"No one else will die, though, and I believe that's what they call a result," Sherlock said, watching as the cabbie moved around to the driver's side door. Aziraphale would have called it a result, at least.

The cabbie's smile was rank with confidence. "You won't ever understand how those people died," he said, as Sherlock's weak reluctance cracked even more as the truth in those words sank in. "What kind of result do you care about?"

Sherlock never claimed to be full of self-restraint. He was a demon, after all.

The man thought he could do whatever it was he did to the human victims. The cabbie thought he could get Sherlock Holmes to kill himself. Sherlock was fascinated. He couldn't resist seeing the human try.

So, he got in the cab and they drove off. Sherlock's heart beat faster with anticipation. This was a rare case indeed to make him react this strongly, even when there was no way this human could have killed him. But that wasn't the point of the cabbie's methods, of course; that was what made it so alluring to an immortal creature like Sherlock.

"How did you find me?" he asked, eyes wandering. The cabbie was clearly a single father, or an estranged one. The shaving cream told him the latter was true.

"I recognized you! As soon as I saw you chasing my cab—Sherlock Holmes," the cabbie said, still far too cheerful. Arrogant for a human of his age and health. "I was warned about you."

Sherlock met his gaze in the rear-view mirror immediately. "Warned?"

That was intriguing. And alarming.

For the first time in several months, a tiny sliver of apprehension entered Sherlock's mind.

"Who warned you about me?" he asked, deliberately indifferent.

The cabbie grinned. "Someone out there who's noticed you."

Noticed?

Oh, dear.

Sherlock contemplated the implications.

"Who would notice me?" he asked, gaze sharper.

"You're too modest, Mr. Holmes," the cabbie replied. "Got yourself a fan."

Fan. Potentially a sarcastic remark; an implied threat. A rival, perhaps. Actual danger…? Possible.

Sherlock sat back and watched the human carefully.

Maybe this wasn't about a clever serial killer after all.

They ended up at the Roland-Kerr Further Education College. A discreet, distant location. Perfect for a murder. Sherlock was particularly amused when the gun came out. It wasn't even _real_.

"Oh, dull," he sighed. Maybe the cabbie didn't know his secret. Suddenly, he felt let down.

"Don't worry," the cabbie promised. "It gets better." He let the gun drop. "Don't need this with you, 'cause you'll follow me."

 _It had better get better_ , Sherlock thought. He willingly followed the cabbie inside the college. The cleaners must have been on the other side of the school, since the second floor was deserted as they commandeered a room.

**0000**

Why did they put up with Sherlock Holmes?

_Because Sherlock Holmes is a great man._

John looked around the empty apartment room and wondered.

_And someday, if we're very, very lucky, he might be a good one._

What did that mean, really? John had known plenty of good men. He had patched them up and watched them die. He had even saved a few, but not enough. He knew what a good man was.

He had never really met a great one, however.

Time passed on in the silence. John stared at the laptop and scowled. It had been twenty minutes already and there was nothing. Not a text, not a phone call, not a trace of the great detective.

Impatience and anxiety tugged at his nerves. John looked out at the door and fought the urge to just go running out onto the streets. Sherlock would probably come rushing in any minute, coat swinging, chastising John for being too slow to follow.

Maybe waiting would be best—

_Ding._

John turned and looked down at the laptop. The map was flashing. Slowly, John realized the phone had stopped again.

He knew where the murderer was.

A chill flashed through his gut and John abruptly felt what could only be a premonition. If he knew where the murderer was, then—

"Sherlock," he said out loud. He spun around and grabbed his coat.

**0000**

The man's insistence on Sherlock dying that night was almost adorable. His desire to find risk in the mundane routine he had devised for himself and his victims was equally pitiable.

The pill was not exactly unexpected. The second one was, but Sherlock had to hide a smile of his own. The man might have been a genius amongst humans. He was nothing to a creature like Sherlock. Poison wouldn't kill him, even if both pills were tainted.

That fact wasn't what kept Sherlock in his seat, waiting for the story to come out of the old man. He was waiting for answers to more important questions.

"Sherlock Holmes, here in the flesh," the cabbie said, gleefully shifting in his seat. "That website of yours. Your fan told me about it."

Yes, the "fan." Sherlock watched the cabbie carefully.

"You are brilliant. You are a proper genius," the cabbie said, eyes twinkling.

There was a story here. A bigger one than just two bottles.

"You risked your life four times just to kill strangers," Sherlock began, eyes narrowed. "Why?"

The cabbie, as if sensing the deflection, nodded at the table. "Time to play."

"Oh," Sherlock said, already turning the tide, "I am playing."

Piece by piece, he disassembled the dying man's life. The estranged children, the clothing, the aneurism—and so came tumbling out the sad man's excuses for murder.

"Because you're dying, you've murdered four people?" Sherlock prompted.

The cabbie's smile finally dropped. "I've outlived four people," he said. His scowl suddenly flared back up into a smirk. "That's the most fun you can have with an aneurism."

Quite the way to look at it. The human had a point, albeit not a very politically correct one. Sherlock let him have that.

"No, there's something else," Sherlock said, still leaning forward on the table. "You didn't kill four people because you're bitter. Bitterness is a paralytic."

If there were any force that could drive a murderer besides anger or hate—

"Love is a much more vicious motivator," Sherlock concluded. It was. For whatever reason, for humans, it was. "Somehow, this is about your children."

And that's how it came down to money.

Why did it _always_ come down to money for humans? It was always the dullest answer for their crimes.

But for this case, it didn't end with money. What was most intriguing was where the money was coming from.

"Not much money driving cabs," the cabbie admitted, softer. "My kids won't get much when I die."

"Not much money in serial killing."

"You'd be surprised."

There it was. The lure. Sherlock leaned closer. "Surprise me," he said, mind on full alert.

The cabbie's smile grew smug. "I have a sponsor," he admitted, leaning closer.

For a full two seconds, Sherlock was significantly distracted.

"And just _who_ would finance a serial killer?" he asked, all at once obsessed.

What an idea. What a superb, fascinating, thrilling idea. If he were a lesser sort of creature, Sherlock might have left this mess in front of him right where it sat and go after this new twist like a dog would a stick. It could have been larger than anything Lestrade brought to his attention. This could have been a case to sate Sherlock's ever-increasing appetite for mystery—

"Someone who doesn't mind riling up a demon or two," the cabbie replied, all too pleasant.

Sherlock froze.

The cabbie grinned. "Weren't expecting that, were you, Mr. Holmes?" he asked.

No. Sherlock slowly clenched his fists. No, he had not. He had almost forgotten the posed threat.

It was back, bolder than ever.

"Who is he?"

"You're not the only one to enjoy a good murder," the cabbie said, smirk incessant.

It could have been another demon, but for what reason would one seek Sherlock out now? An angel would never bother with theatrics like this. Crowley had slipped up somewhere.

Unless it was a hunter.

Sherlock fought the urge to tear out the man's throat on instinct.

Perhaps he should have called Lestrade in when he had the chance. Aziraphale should have picked up on this. Their cover was compromised.

"You're not just a man," the cabbie said. He didn't seem scared at all. Death made humans so damn irritating. "But there's so much more to them than that."

More than one? A band of hunters? A group of demons? Sherlock tried to find a clue in the man's words, but nothing stood out.

"What do you mean?" he asked, holding back on his emotions. He needed answers. Now. The case was no longer important, no matter what his curiosity demanded. He had to focus.

"There's a name that no on says." The cabbie shrugged. "And I'm not going to say it either."

With that, Sherlock was done playing games. He grabbed the pathetic excuse for a gun and crushed it in his hand. The cabbie flinched back and Sherlock glared as he flicked metal and lighter fluid across the table in disgust.

"Well, this has been very interesting," he said coldly, standing. "But if you don't start explaining who you are working for, I will have to force you to."

Even under his shadow, the cabbie didn't falter. "What's the matter?" the human said, the only sign of duress in his eyes. It wasn't from fear. Sherlock couldn't read it. "Can't figure out which bottle is what?"

"I have had _enough_ games," Sherlock began. He couldn't ignore this threat. Something had leaked. It was time to plug the hole—

"Or maybe you haven't," the cabbie said, interrupting his thoughts. "Maybe you just can't figure it out."

Sherlock froze.

"The great Sherlock Holmes, the great detective," the cabbie continued, willingly taunting a being ten times his worth and strength. "The demon who can't outsmart a little dying cabbie."

Sherlock stared at him.

When had he gotten this weak? Especially when it mattered?

"Come on," the cabbie goaded. "Play the game."

It was a game.

Humans always came up with the best games.

He reached out and took the bottle closest to the cabbie.

"I bet you get bored, don't you? I know you do. Creature like you, so clever."

He could have taken the pill. It didn't matter if he chose wrong. It wouldn't kill him. But there was no reason to take the risk, to encourage a murderer to kill himself with the other pill.

"But what's the point of being clever if you can't prove it?"

Sherlock stared at the little white pill and considered.

"After all these millennia, and you're still just a wild animal addicted to _this_. You'll do anything at all, to stop being bored. You must be bored, since you have seen it all."

There was no way that he was wrong. Because if anything, humans were understandable. They were easy to read. They were predictable—

Sherlock dropped the pill at the sound of a bullet crashing through two glass panes and then solid flesh—and the cabbie dropped.

All at once, the thrill of the chase died and Sherlock realized his greatest mistake.

He stalked over to the downed human bleeding out on the floor. A gunshot to the shoulder; too close to the heart. The man was dying. Luckily, his life wasn't quite through being useful.

"Okay, tell me this," Sherlock began, crouching over the human, who was wheezing. "Your sponsor—who was it? The one who told you about me, my fan? I want a _name_."

He had to know, to be able to tell the angel and Crowley. They had to know who their enemies were, with the End creeping up on them once more.

Sherlock Holmes was not done living the life of Sherlock Holmes. No hunter, angel, or demon would take that from him.

The cabbie shook his head and looked away. Sherlock snarled.

"Who hired you? !" he asked, baring his teeth.

Who dared to confront a demon? Who dared to seek him out? Who dared to threaten the West Wind?

Sherlock stomped onto the bleeding wound and the cabbie howled a name out, only once.

" _Moriarty_!"

A name that meant nothing to him. Not now, at any rate.

Dissatisfied, Sherlock stepped back and watched the man struggle to breathe. It would have been a mercy to kill him then.

But he didn't. Sherlock didn't kill humans anymore.

He was not known to be a merciful creature either.

The cabbie took one last breath and then it was over. Sherlock stared at the corpse as red and blue lights flashed through the windows and splashed onto the walls.

_Moriarty._

**0000**

Sherlock Holmes was officially the strangest man John Watson had ever met, human or no.

Because really, the eyes had been one thing. His brother was something entirely different.

"Was that man really your brother?" he asked, glancing back repeatedly as they moved away from the crime scene. Being away from the flashing lights and potentially observant police officers was better for John's nerves, but being watched like that by a creepy guy in a suit wasn't soothing either.

All of the mystery, all of the talk of archnemeses, all the bluster—and it had been Sherlock's brother?

Since when did demons have _brothers_?

Or…a _Mummy_?

Sherlock sighed, overly dramatic. "Yes, unfortunately," he replied, as if it was a painful annoyance just to admit aloud.

John couldn't really see Mycroft's face any more in the shadows. "Is he… you know…?" he started to ask, before he realized how stupid the question was.

Sherlock, thankfully, caught on and didn't chide him for his curiosity. "Human? Yes, he is utterly human, the bore," he said, again with disdain. "Don't pay him any mind."

His brother was human, but Sherlock…wasn't? John stopped trying to look back but still felt Mycroft's distant gaze on him.

"Consider me adopted, if that helps," Sherlock added with a shrug.

John nodded vaguely. "I see." Well, he would have to believe it. He certainly wasn't going to be seeking Mycroft out to confirm it later.

Sherlock wanted to go get food. He seemed entirely healthy and content. John didn't want to dwell on what had happened forty minutes ago, so he was glad for a distraction.

He was even more glad that Sherlock had kept silent about it before when it had mattered, with Lestrade. John felt the heavy weight of the pistol in his pocket sink down more against his side.

Still, as much as he would like to pretend the burning sensation in his hand had nothing to do with the adrenaline rush he had experienced earlier, and that neither feeling felt _good_ —he still had to dwell on the incident a little bit longer.

"Really, though, are you alright?" he asked, squinting at the taller man. He had seen a flash of white, the pill, but he hadn't asked if the cabbie had done anything else. Then again, he had no idea if Sherlock could even _be_ hurt.

"Oh, yes, I'm fine," Sherlock replied dully. "Not a scratch."

Despite not exactly trusting the man's honesty, John nodded. "Good."

Adjusting his scarf, Sherlock suddenly gave John an odd look. "You knew I wasn't human, and yet you were concerned enough to…act," he said, voicing a question beneath that statement. He was asking why.

"I…" John hesitated over an answer.

He had seen Sherlock with who could have only been the serial killer. He had seen a flash of white in Sherlock's out stretched hands, which could have only been a pill. It had been instinctual.

His spontaneous reaction really had nothing to do with being a human or something else, John realized. It had everything to do with the fact a man he knew was facing down potential danger.

"The poison wouldn't have killed me," Sherlock said.

John frowned. "Oh."

"Yes…" Sherlock cleared his throat. "At any matter, thank you."

"Why? It didn't matter anyway," John said, curious. Why would he be thanking John for something that wouldn't have affected him? Sherlock didn't seem like the sort of person who'd be thankful for that.

Sherlock shrugged. "Isn't that what you people say—it's the thought that counts?"

John didn't reply. He took it at Sherlock being nice not for the sake of being nice, but for the sake of being nice to John. Why, he was still trying to fathom.

Some of Sherlock's odd behavior made sense now, when he thought back to their previous encounters.

_Breathing. Breathing's boring._

The amount of nicotine patches.

The intense stare that felt like it was piercing his soul. Maybe it was.

Some things, however, were still questionable about Sherlock's nature. Like why Sherlock Holmes had asked for a human roommate and why he tolerated a man like John.

When he finally asked then, Sherlock surprised him once more.

"I need someone to cover me," Sherlock explained.

"Cover you?"

"Living as a genius at the residence of a kindly old woman isn't going to work now that I'm working on criminal cases outside the home," Sherlock said, turning his head to look back at the police gathered around the college. "I might slip on the job, or use a power that will make it easier to spot me out in the open. It is more likely people will notice my, shall we say, noticeably inhuman actions through conversation. Those moments do linger in peoples' memories most, so I may be exposed incidentally through investigations."

John hesitated. "What do you need cover from?" If a pill full of poison or serial murderers didn't scare him, what else was out there?

"There are other demons and monsters, John," Sherlock said, as simply as he might have explained away his brother's presence. "Far worse than me. I've spent the last few decades hiding from them the best I can."

Suddenly, the vacancy at the prime real estate of 221B Baker's Street made so much more sense.

"…Oh." John swallowed, a nervous feeling settling in his gut now. "What good would having me along do, though?"

He could shoot, obviously, but he was…just…human. Didn't that, well, _matter_?

"I need to look normal. Having someone else along, a human, helps me to blend in more. Apparently." Sherlock said that with a sneer, as if someone else had told him that. It intrigued John more than the threat of whatever Sherlock was hiding from did. "Any remaining oddness I might let slip will hopefully be shielded by your normalcy. In theory."

John _was_ painfully plain. "I see."

"It's not the safest job," Sherlock said, looking at him pointedly.

The serial murderer lying dead half a mile back was sort of a giant example.

"…You think I'll take it anyway?" John asked, glancing back at the demon.

Sherlock, in turn, smiled smugly. "How's your limp, doctor?"

John glared. "Shut up." Sherlock just laughed.

The detective led them both on toward the end of the block and John was left to ponder it all in silence. It was a lot to take in and digest. His hand was still buzzing from where his gun had fired.

"Sherlock…" he began.

"Hmm?"

John sent the demon a careful look. "So, these cases… are something that I'm going to have to get used to, living with you and Mrs. Hudson?"

Sherlock didn't hesitate. "Naturally."

"Oh…" John nodded slowly. "Good."

It was good, in a way that John really couldn't explain.

"You are taking this well," Sherlock said, eyebrow up.

"Well, it's like I said before," John said, hands in his pockets. "It's all fine."

Sherlock held his gaze for a moment. "Good," he said. He suddenly picked up his pace and smiled. "Come on, I know a short cut."

John only took a few seconds to watch him go before smiling to himself and following. His hand still itched.

Somehow, it was all fine.

**0000**

**Two Days Later  
221B Baker's Street**

"So, is he staying?"

Sherlock sent the fidgety old woman a strained glare. "Not that you need to concern yourself over it," he replied. "But, yes, he is."

John was out finalizing his departure from the veterans' housing. Most of his belongings had already been moved into the spare room upstairs. Sherlock had been enjoying his last few minutes of solitude with his violin, when of course, the angel had to interrupt.

"Oh, that's wonderful!" Mrs. Hudson said, hands clasped together. "He seems like such a nice fellow. But, ah, you're sure...?"

"I'm sure _what_?" Sherlock asked, plucking a harsh note.

Mrs. Hudson sent him a kind look, but he could see a more severe glint in her eyes. "Sherlock, I know you're doing your best, and I am sincerely impressed you've done as well as you have, even without Crowley or I interceding," she began, "but perhaps befriending a human for this, bringing him here as a roommate, is, well, a bit rushed. I can only keep so many humans in the dark, so you need to make sure he's the right kind before you let him live among us—"

Sherlock sat back and bowed out a few staves of Mozart. "He knows."

The older woman paused. "…Already?"

"Yes."

Mrs. Hudson stood up straight. "My, and he hasn't gone running?" She beamed; her reaction was exactly opposite of what Crowley's would be. "If he wasn't human, I'd say you've found yourself a keeper!"

" _Do_ shut up, angel," Sherlock snarled.

"No need to get nasty," Mrs. Hudson sniffed. She put a hand on her hip. "Please do exercise caution, for both of our sakes, Sherlock. I can keep us off the radar at least until—you know—but I'd rather not have to explain to my superiors why a human _and_ a demon are running about my property together. Or having Lestrade involved again. That was just unnecessarily messy."

Hunters were always a potential threat, but not more than the angel's _friends_ were.

"You don't need to tell _me_ about exercising caution," Sherlock replied, scowling. "We've survived this long, Aziraphale, due to my intellect."

" _Or_ rather our collective luck. Never mind." Mrs. Hudson sighed. She suddenly perked up. "Do you suppose he likes biscuits? I'll put a pot on while he moves on in..."

Sherlock rolled his eyes and collapsed back into the seat. "Ugh."

Now, he just had to call Crowley.

Later, he decided. He picked up the bow again and smiled to himself.

A companion, a new mystery, and an older case solved—

Things were radically looking up.

  
**End** _**First Impressions** _ **.**  


**Author's Note:**

> Next, a boy meets a demon at a crossroads. Somehow, it does not go according to plan.
> 
> A/Ns:  
> -Yes, Lestrade knows about Sherlock now. There's been about a year's jump between this segment and "Building Down." More to come on that moment in another one shot, "Skeletons."  
> -Yes, Mrs. Hudson = Aziraphale. Wait for ittttt…  
> -Where is Crowley? Why are Aziraphale and Sherlock living together? Where does Moriarty fit into this? Lestrade? Etc etc… just wait for more installments. All shall be explained.


End file.
